Improved method of recovering grease from waste soap-liquors



tell fitattt 33mm one.

WILLIAM KOEHLER, 0F NORWALK. CONNECTICUT, ASSIGNOR TC J CHN M. PENDLETON.

Letters Patent .No. 96,241, dated October 26, 1869.

IMPROVED METEOD OI ,RECOV ERII NG GREASE FROM WASTE SOAP-LIQUORS.

The Schedule referred to in these Letters Patent and making part ofthe same To all whom it may-concern.-

Be it known that I, WILLIAM Kosnnnn, of Norwalk, in the county of Fairfield, and State of Connecticut, have invented a new and improved Method of.

Recovering Grease from Waste Soap-Liquors; and I do hereby declare that the following is a full and correct description of the same.

I will first describe my process, and what I consider to be the best means of carrying my invention into practical use, and then designate the points wherein I believe it to be new.

I collect the waste soap-liquors from the woollen mills into large tanks or casks, holding about twenty barrels each, and into each cask I stir four quarts of salt-spent lye, which I obtain from soap-factories, and which is otherwise generally thrown away. Allowing the mixture to stand for about one-quarterof an hour, I then add two quarts of sulphuric acid, mixing well, asbefin-e. In the course of six to ten hours, a separation will be found to have taken place, the grease and suds rising to the top of the cask. The water is then drawn oil from the bottom of the cask, and is still further removed from the residuum by means of burlap-strainers, which will allow only the water to pass through, leaving a jolly-like mass, somewhat resembling thick mud. This substance is then shovelled into press-cloths or bags, ordinary unbleached sheet-- ing being generally preferred, about thirty pounds being placed into each bag. The bags are then arranged in a box or kettle, and clear water is poured in till the bags are covered, when heat is applied, so as to boil the water. At the same time with the boiling, pressure is applied to the bags, bymeans of a screwpress, or any other convenient method, which causes the grease to exude from the bags, and mingle with the water. The pressing and boiling are continued until the grease is sufficientlyremoved, which will generally require about six hours. As soon as the boiling ceases, the grease separates from the water, and is drawn oil separately, andpreserved. The grease, adhering to the press-cloths and sides of the box, is removed, and secured, by introducing hot steam into the box.

I am aware that waste soap-liquors have been collected before, and the grease separated and recovered by means of treating the liquors, with sulphuric acid, and pressing the jelly-like mass in a steam-chest; but the peculiarities of my process render its advantages apparent in the increase of yield, the greater purity of the product, and great reduction of expense, which render the collection of grease in this way practicable. By my process, about one-half of the expense in the amount of acid required is saved, while there is an in crease of at least five per cent. in the yield. The

greater purity of the grease recovered also renders it worth from ten to twenty per cent. more than that obtained by theold process.

The press-cloths or bags are found to last .much longer, not being eaten by the acid, as was formerly the case in the old process.

Having now fully described my invention, and stated its advantages over other similar processes in use,

What I claim as new, and desire to secure by Letters Patent, is-

1. Ihe use of a solution of alkali and salt as an agent in assisting to recover grease from waste soapliquors.

2. The pressing of the jelly-like mass, which is obtained from soap-liquors, while immersed in boiling water, substantially in the manner and for theopurpose specified.

WILLIAM KOEHLER.

\Vitnesses:

J soon TURK, Enwo. P. WEED. 

